nutrition and gas exchange in plants- topic 7

• waxy cuticle, prevents water loss by evaporation, aquatic plants do not have a waxy cuticle
• importance of photosynthesis, light energy (sun) chemical energy (glucose)
• three uses of glucose are sucrose, starch and cellulose
• nitrates required for amino acids of proteins for healthy plant growth
• waster products of metabolism are, oxygen released out of the stomata
• if it gets too cold the rate of photosynthesis will decrease however plants cannot photosynthesise if it gets to hot
• without enough light a plant cannot photosynthesise very quickly, increasing light intensity will boost rate of photosynthesis
• even if there is plenty of light a plant cannot photosynthesise if there is insufficient carbon dioxide
• magnesium required to make chlorophyll, chlorophyll is required for photosynthesis
• spongy mesophyll not packed tightly together allows the movement of gasses to and from the cells
• palisade cells top layer, have many chloroplasts to catch sunlight are blocked shape so can pack many
• photosynthesis equation carbon dioxide+water-glucose+oxygen
• plants have leaves as leaves are used to take in co2 and capture sunlight which is needed for photosynthesis
• stomata are pores which allow for gas exchange, to limit water loss the top of the leaf is more exposed to the sun and wind which increases rate of transpiration
• stomata are open when turgid
• stomata are closed when flaccid
• photosynthesis carbon dioxide in, oxygen out
• respiration oxygen in carbon dioxide out